Go Tell It On the Mountain! Folk singer Mary Travers is 69 today. One-third of the trio Peter, Paul and Mary, Mary grew up in a socially-aware family of activists. She, Peter Yarrow and Noel "Paul" Stookey formed their singing group in 1961 and quickly became known for their strong social consciousness and beautiful harmony. Some of their most famous songs are "Blowin' in the Wind," "Puff, the Magic Dragon," "The Hammer Song" and "Where Have All the Flowers Gone?"